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Hematology

What is hematology?

Hematology is the study of blood and blood disorders. Hematologists and hematopathologists are highly trained healthcare providers who specialize in diseases of the blood and blood components. These include blood and bone marrow cells. Hematological tests can help diagnose anemia, infection, hemophilia, blood-clotting disorders, and leukemia.

What is the difference between a hematologist and a hematopathologist?

A hematologist is usually a board-certified internist, or pediatrician who has completed additional years of training in hematology. The hematologist generally focuses on direct patient care and diagnosing and managing hematologic disease, especially cancers.

A hematopathologist is usually board-certified in both anatomical and clinical pathology and has additional years of training in hematopathology. Hematopathology is not only the study of disease of the blood and bone marrow. It is also the study of the organs and tissues that use blood cells to perform their physiologic functions. These include the lymph nodes, the spleen, thymus, and other lymphoid tissue. The hematopathologist focuses on the diagnosis of conditions of the hematopoietic and lymphocyte-rich tissues. This is usually done by direct exam of tissue and blood in the lab.

Common hematology tests

Test

Uses

Complete blood count (CBC), which includes:

White blood cell count (WBC)

Red blood cell count (RBC)

Platelet count

Hematocrit red blood cell volume (HCT)

Hemoglobin concentration (HB). This is the oxygen-carrying protein in red blood cells.

Differential white blood count

Red blood cell indices (measurements)

To aid in diagnosing anemia, certain cancers of the blood, inflammatory diseases, and to monitor blood loss and infection

Platelet count (usually done as part of the CBC)

To diagnose and/or to monitor certain types of bleeding and clotting disorders

Prothrombin time (PT)

Partial Thromboplastin Time (PTT)

International Normalized Ratio (INR)

To evaluate bleeding and clotting disorders and to monitor anticoagulation (anticlotting) therapies

Bone marrow biopsy is not a common test in general, but is a common test for hematologists. It involves taking cells from the bone marrow for analysis for many types of disease.